Chain link



Oct. 10, 1950 c. E. ANDERSON ETAL CHAIN LINK Filed May 1, 1946 Patented Oct. 10, 1950 OFFICE CHAIN LINK Carlos E. Anderson and Charles E. Sennholtz, Chicago, Ill.

Application May 1, 1946, Serial No. 666,392

2 Claims.

The present invention relates generally-to improvements in link chains adapted for heavy duty service, such, for example, as chains commonly employed for ship anchors and drag ,linejexcavator buckets, and has particular reference to a new and improved design of the interengaging chain links.

One of the objects of the present invention is to provide a novel chain link which for a given size is exceptionally strong and particularly resistant to wear and shock.

A further object is to provide a novel chain link having openings at opposite ends which are shaped to guide the ends ofythe interconnected links expeditiously into end bearing engagement upon the application of a longitudinal pull on the chain, thereby avoiding kinking and tangling.

Another and more specific object is to provide a new and improved chain linkhaving opposite end openings for the reception of contiguous links which provide ample space or clearance for casting the links initially in a chain series. In general, one of the primary and more specific objects of the invention is to provide a novel chain link of a sectional design in which the metal stock is provided where most needed, i. e.,

where the most wear ordinarily occursso as to Y obtain maximum strength and maximum life. Other objects and advantages will become apparent as the description proceeds In the accompanying drawings:

bodyingthe features of the present invention.

Fig. 2 is a face view, on an e larged scale, of L one of the chain links.

Fig. 3 is a transverse sectional View of the link taken along line 3-3 of Fig. 2.

ance is provided between the adjacent surfaces thereof to aiford the necessary sand room in the casting operation. One of the important objects of the present invention is to provide the metal stock where it is most needed so as to obtain maximum strength and the longest possible life for a given size, and, at the same time, provide adequate clearance for sand room, particularly between the curved ends I.

Fig. 4 is an enlarged fragmentary sectional view illustrating the bearing contact between two interconnected links in the medial plane of one of said links.

Fig. 5 is a view similar to Fig.4; but taken along 5-5 of Fig. 4 to illustrate the bearing contact between the links in the medial plane of the other of the links.

' Referring more particularly to the drawings, the chain link constituting the exemplary embodiment of the invention comprises a continuous oblong loop of integral construction having side bars 6 connectedby curved ends I. Preferably, the side bars 6 are additionally connected and reinforced by an intermediate transverse tie bar or strut 8 bisecting the open area circumscribed by the loop. When provided, the tie bar or strut 8 serves to define two. openings 9 and Ill at opposite ends of the link for receivin'gthe curved ends I of the adjoining links.

When a series of the links are interconnected to form a chain, as fragmentarily illustrated in The link is formed with flattened parallel side faces I I and I2. As a result, the flat sides of the curved ends 1 of each link can be adequately spaced from the inner surfaces of the side bars 6 of the adjoining links, to provide the necessary area of the curved ends 1 can be made comparatively wide, as indicated in dotted outline in Fig.

2. If the transverse formof the curved ends i were circular, the permissible sectional area would be considerably less.

The curved ends 1 are formed with inner bearing surfaces M which are symmetrically arcuate about equal radii R and R both in the general plane of the link and in any radial plane perpendicular thereto through the center of transverse curvature.

, The curved ends 1 also are formed with outer surfaces l5 which are likewise .arcuate, and preferably described about the same center as the surfaces M in the general plane of the link. The surfaces l5 are not required to bear against any other portions of the adjoining links, but are normally exposed to extraneous wear in rough usage of the chain. Hence, it is desirable to provide the surfaces [5 withadditional metal at the outer edges. The transverse shape of these sur- 'when subjected to a heavy pull. because of the faces l4.

; tension load at. the outer surfaces l5 than because of the compression load at the-inner sur- One. of the primary features of the invention is to so shape the openings 9 and Ill in the link that when the chain is tightened, the side bars 3 6 will tend to guide the curved ends 1 directly into centered bearing engagement. To this end, the inner arcuate surfaces I 4 are formed with a relatively small radius, and extend only along a short arcuate segment AA of the link, for example through 90, corresponding approximately to the thickness between opposite faces I l and I2, there by narrowing the outer end portions of the openings. From and beyond the opposite ends of the arcuate segments AA, the adjoining portions [6 of the sides of the openings 9 and I2 continue to diverge inwardly, and preferably are arcuate in form'along segments A-B in the general plane of the link, while the transverse curvature remains the same as that of the surface I l. The arcuateside portions l6are eccentric to the surfaces M and in each instance struck on a longer radius located at one side or the other of the longitudinal medialaxis of the link. In the present instance, each of thearcuate segments AB of the linkextends through approximately 45. The outer surfaces of the curved ends beyond the segment A-A preferably are concentric to and coextensive with the surfaces 16 in the general plane of the link.

From and beyond the arcuate segments AB, the inner portions of the sides of the openings 9 and still continue to diverge in the general plane of the link along sections BC, but at a lesser degree than the segments AB. The sections BC may have any desired inside contour, and in the presentinstance are shown as formed of straight-line longitudinal elements. Here again, the transverse curvature may remain the same as that of the surfaces It. At the extreme innerends of the sections BC, the sides of the openings .9. and IE! are connected through rounded corners 18 to the sides of the tie bar 8. In gen eral, sharp corners. are avoided throughout the link in order to eliminate the tendency which such corners. have to develop cracks. By reason of the special shape of the openings 9 and iii, the inner side surfaces I1 and i6 converge from adjacent the tie bar 8 continuously and at an increasing rate outwardly toward the comparatively narrow end bearing surface l4, and hence tend to cam or direct the interconnected arcu'ate ends '1 immediately into engagement whenever the chain is tightened longitudinally.

The outside curved surfaces of the ends of the link, from the segments AB, run out and merge into the side bars 6. These side bars are normally not in bearing contact with any portionof the adjoining links, but are exposed to extraneous wear in rough usage of the chain. Consequently, the side bars 6 preferably are formed with flat outside surfaces l9 and square corners to provide extra metal at the marginal edges, thereby increasing the cross-sectional area to obtain greater strength and durability.

It will be evident that we have provided a new and improved chain link which for a given size and weight has a large cross sectional area through the side bars and ends, and which is provided with added metal where most needed to improve the strength and durability of the chain. The opposite end openings 9 and lil are so shaped that ample sand. room I3 is provided without impairing the strength of the link, and that the slack in the chain is readil taken up without any tendency of the links to kink.

We claim as our invention:

1. A chain link in the form of a closed elongated loop having parallel side bars, curved opposite link ends, and a transverse tie bar connecting said side bars, the inner surface of each of said ends in the general medial plane of said link being concavely curved symmetrically along a central arc struck on a relatively short radius on a predetermined center and extending through approximately and being transversely convexly curved in any radial plane through said center on a radius substantially equal to said first mentioned radius, and then being curved at opposite ends of said central are along contiguous arcs struck in said medial plane on equal radii longer than said first mentioned radius and each extending approximately through 45, the outer surface of each link end being curved in said medial plane about said center and being transversely convexly curved in any radial plane through said center on a radius longer than said first mentioned radius, the inner surfaces of said side bars in said medial plane of said link being oppositely and equally inclined to diverge uniformly from said contiguous arcs in a medial direction toward the center portion of said link, said loop having fiat parallel opposite faces extending substantially throughout said side bars, link ends and tie bar, said side bars having fiat outer sides and substantially square outer corners and transversely convexly curved inner sides, the thickness of said link being substantially equal to the chord subtended by said central arc.

2. A chain link in the form of a closed elongated loop having parallel side bars and curved opposite link ends, the inner surface of each of said ends in the general medial plane between the opposite faces of said link being concavely curved symmetrically along a central arc struck on a relatively short radius, and then being curved at opposite. ends of said are along contiguous arcs struck in said plane on equal radii longer than said first mentioned radius, the inner surfaces of said side bars in said plane of said link from said contiguous arcs being oppositely and equally inclined'to diverge uniformly from said contiguous arcs in a medial direction toward the center portionof said link, the thickness of said link being substantially equal to the chord subtended by said central are, said inner surfaces of said ends and side bars being curved convexly transversely, the outer surface of each of said ends in the transverse plane of said link being concentric to said central arc, and in all radial planes through the center of said central are .perpendicular thereto being convexl curved along an are on a radius longer than said first mentioned radius, the outer sides of said bars being substantially flat and formed with substantially square corners.

CARLOS E. ANDERSON. CHARLES E. SENNHOLTZ.

REFERENCES CITED The following references are of record in the file of this patent: 

